Adeno-associated virus (AAV) is small safe viral vector that has been previously used to deliver antibodies in vivo (Fang et al. 2005). In the context of passive HIV immunization, Johnson and colleagues used AAV as a viral vector for delivery of antibody-like proteins that protected macaques from SIV infection (Johnson et al. 2009). More recent work has also demonstrated that AAV vectors expressing a HIV neutralizing antibody is able to protect humanized mice from HIV-1 infection (Balazs et al. 2012). This research is designed to further assess AAV-delivery of additional broadly neutralizing antibodies. Administration of AAV vectors expressing HIV neutralizing antibodies are being tested to demonstrate their potential for sustained expression and their ability to confer long-lived protection against HIV infection and progression of disease.A major goal is to develop AAV vectors expressing multiple antibodies to increase the breadth of passive immunization therapy to cover strains resistant to any one neutralizing antibody.